Tris{2-[N-(diethylaminothiocarbonyl)benz(-amidino; imidoxy; -imidothio)-N '-yl]ethyl}amines - New tripodal ligands. Synthesis, complex stability, andextraction behaviour of their silver(I) complexes

N-(Thiocarbamoyl)-benzimidoylchlorides react with trivalent nucleophiles to give four novel tripodal ligands. Two of them have been characterized by X -ray methods. The ligands form with silver(I) cationic mononuclear complexe s in which the three arms of the ligand are coordinated monodentately via s ulfur. The results of FAB and ESI mass spectrometry as well as ESCA and NMR investigations verify this binding mode. The protonation constants of the ligands and the stability constants of silver(I) complexes have been determ ined potentiometrically. The novel tripodal compounds behave as powerful ex tractands for silver(I).